Sound Damper for Compressed Air Systems of Vehicles

ABSTRACT

The invention relates to a sound damper for compressed air systems of vehicles. Said sound damper comprises a housing ( 1   a,    1   b ), damping means ( 2 ) and at least one strut ( 3   a,    3   b,    3   c ). According to the invention, the housing ( 1   a,    1   b ), has an air inlet ( 4 ) and an air outlet ( 5 ), the damping means ( 2 ) are boated in the housing ( 1   a,    1   b ) and the strut or struts ( 3   a,    3   b,    3   c ) is or are located in the housing ( 1   a,    1   b ) in such a way, that it or they protrude at least partially into the damping means ( 2 ). Air that flows through the housing ( 1   a,    1   b ) from the air inlet ( 4 ) to the air outlet ( 5 ) is conducted by the strut or struts ( 3   a,    3   b,    3   c ). into the damping means ( 2 ).

The invention generally relates to embodiments of a sound damper for compressed air systems of vehicles, which comprises a housing and an insulating means, the housing having an air inlet and an air outlet, and the insulating means being arranged inside the housing, so that air which flows from the air inlet to the air outlet through the housing flows through the insulating means and sound damping is thereby achieved.

Sound dampers of the general type under consideration are suitable particularly for use in venting the compressed air system, in order to damp the noises generated when the compressed air system is being vented.

Sound dampers of this general type are disclosed, for example, in DE 102 48 183 A1 and DE 20 2004 011 630 U1.

The disadvantage of known sound dampers of this type is that there is the possibility that at least part of the airstream flows past the insulating means or flows under it, with the result that the damping properties of the sound damper are reduced.

An object of the present invention is, therefore, to provide a sound damper which ensures an effective conduction of the airstream through the insulating means of the sound damper.

This object can be achieved by means of a sound damper according to independent claim 1.

Advantageous embodiments are the subject matter of the dependent claims.

The sound damper according to the claimed invention comprises a housing, an insulating means and at least one web, the housing having an air inlet and an air outlet, the insulating means being arranged inside the housing, and the at least one web being arranged inside the housing such that said web projects at least partially into the insulating means, and air which flows from the air inlet to the air outlet through the housing being conducted into the insulating means by the at least one web.

The term “project” is to be understood in this context to mean that, at least in the portion in which the web projects into the insulating means, the insulating means is adjacent on both sides to the opposite side faces of the web. Preferably, the entire outer face of that portion of the web which projects into the insulating means is adjacent to the insulating means.

The at least one web ensures that the airstream flows through the insulating means as effectively as possible, in particular part of the airstream does not flow under the insulating means. However, the form of the web, in particular the height and/or diameter, may vary, depending on the set-up of the sound damper.

Preferably, the at least one web is formed in one piece with the housing. For example, the housing may be composed of a cover and a bottom, the at least one web being integrally formed on the bottom and/or on the cover. In this case, the web would even be formed in one part with the housing. This is preferred since it is cost-effective.

Preferably, a first web surrounds the air inlet and/or a second web the air outlet.

By means of an arrangement of this type, the air, on its way from the inlet to the outlet, has to flow around the first web and/or the second web. The airstream is thus conducted effectively into the insulating means. Basically, it is also possible that the inlet and outlet are surrounded by a web in regions only, so that only part of the airstream is routed by the web.

Preferably, the housing and the at least one web are designed to be radially symmetrical about a common axis. Basically, of course, other forms are also possible, in particular oval or rectangular forms.

Preferably, the insulating means contains a knitted roll composed of a knit material wound about an axis. Basically, the invention can also be used with other insulating means. In particular, a plurality of insulating materials may be provided.

Preferably, the knitted roll and the at least one web are arranged so as to run parallel to one another. This makes it easier to arrange the web and knitted roll, in particular to carry out mounting, since the web can press one or more rings of the knitted roll away or together. Preferably, all the webs run parallel in this way. Preferably, the at least one web, the housing and the knitted roll are arranged along a common axis of symmetry, the web and housing being designed to be radially symmetrical. This makes it possible to have a highly compact form of the sound damper.

Preferably, the at least one web tapers at its end projecting into the insulating means. This makes it easier to introduce the web into the insulating means during mounting. Basically, however, other forms are also possible, for example a rounded, serrated, straight or wavy form.

Preferably, the at least one web has, in the region of its end projecting into the insulating means, one or more emergency passages for the passage of air. Emergency passages of this type are formed preferably by geometric orifices on the web edge, the orifices being formed in such a way that, if the sound damper is iced up, these are broken out by being subjected to a dynamic pressure and a channel for the airstream is thus opened up.

Preferably, the air outlet comprises at least one venting slot. A multiplicity of narrow elongate venting slots can be provided, particularly in order to allow rapid venting.

Preferably, the sound damper has a screen element which is arranged in the region of the air inlet. A screen element of this type serves for throttling the airstream prior to entry into the insulating means. This screen element may be an element independent of the housing or else be formed in one piece or in one part with this.

The housing, web and screen element are preferably composed of plastic. Basically, other materials can also be used, for example metal, in particular aluminum, or else even material combinations.

The invention, then, is explained in more detail by means of an exemplary embodiment which is illustrated by a FIGURE.

The FIGURE shows a view of a partially cut away sound damper according to an exemplary embodiment of the invention for compressed air systems of vehicles. In this case, the sound damper is arranged in the venting of the compressed air system in order to damp the venting noise when the compressed air system is being vented.

The sound damper comprises a housing, an insulating means 2 and three webs 3 a, 3 b, 3 c. The housing is constructed in two parts from a cover 1 a and a bottom 1 b. Located in the bottom 1 b is an air inlet 4 and in the cover 1 a an air outlet 5.

The insulating means 2 is arranged inside the housing 1 a, 1 b. The three webs 3 a, 3 b, 3 c are arranged inside the housing 1 a, 1 b such that they project into the insulating means, and air flowing from the air inlet to the air outlet through the housing 1 a, 1 b is conducted into the insulating means by the webs 3 a, 3 b, 3 c.

The webs 3 a, 3 b, 3 c are formed in one piece with the housing 1 a, 1 b. The web 3 a is formed in one part with the cover 1 a and the webs 3 b and 3 c are formed in one part with the bottom 1 b.

The housing 1 a, 1 b and the webs 3 a, 3 b, 3 c are designed to be radially symmetrical about a common axis of symmetry 6. The cover 1 a of the housing has essentially the form of a pot, and the bottom 1 b of the housing is essentially planar. The air inlet 4 is formed as a circular orifice, likewise with the axis 6 as an axis of symmetry, in the bottom 1 b. (Alternatively, the air inlet 4 can also be designed to be offset with respect to the axis 6). This circular orifice is completely surrounded at its margin by the annular second web 3 b which projects into the interior of the housing.

The air outlet 5 is formed by a multiplicity of narrow elongate venting slots which are arranged so as to run radially with respect to the axis of symmetry 6 and which commence in the marginal region of the bottom of the housing cover 1 a and extend over a large part of the cover outer face. The venting slots 5 are completely surrounded radially by the first web 3 a, and the web 3 a is designed as a ring on the bottom of the housing cover 1 a, said ring being adjacent to the start of the venting slots 5, and projecting into the housing interior.

The third web 3 c is formed at the margin of the housing cover 1 b, the diameter of which is somewhat smaller than the inside diameter of the housing cover 1 a. The third web 3 c likewise projects into the housing interior.

The air inlet 4 is covered completely by a screen element 7. This screen element 7 has a multiplicity of circular continuous orifices. The purpose is to throttle the airstream of the compressed air system during venting. The sound damper is connected to the venting of the compressed air system via the screen element 7. It is likewise possible to design the sound damper without a screen element.

The insulating means 2 is a knitted roll composed of a knit material which is wound about an axis and which comprises thermoplastic threads. Alternatively, in particular, metal can also be a possible material. The knitted roll 2 and the webs 3 a, 3 b, 3 c are arranged so as to run parallel to one another, the axis 6 therefore being a common axis of symmetry.

The webs 3 a, 3 b, 3 c are tapered at their end projecting into the insulating means 2, see, for example, the end 8 a. Furthermore, the webs 3 a, 3 b, 3 c have, at the edge of the end projecting into the insulating means 2, a plurality of emergency passages (not shown) for the passage of air.

The diameter of the second web 3 b designed to be radially symmetrical is somewhat smaller than the diameter of the first web 3 a designed to be radially symmetrical. The first web 3 a and second web 3 b in this case project deeply into the insulating means 2, but do not overlap one another in height. This arrangement of the first web 3 a and of the second web 3 b forces an airstream to flow around the second web 3 b, pass through the narrow passage between the ends of the first web 3 a and of the second web 3 b and flow around the first web 3 a in order to pass from the air inlet 4 to the air outlet 5. This has the effect that an airstream is conducted effectively through the insulating means 2. The third web 3 c, which has a diameter larger than the diameter of the annular web 3 a, contributes to conducting the airstream through the insulating means 2 in the direction of the venting slots 5.

The housings 1 a, 1 b, webs 3 a, 3 b, 3 c and screen element can be produced from plastic, in this case from polyamide. 

1. A sound damper for compressed air systems of vehicles, which comprises a housing (1 a, 1 b), an insulating means (2) and at least one web (3 a, 3 b, 3 c), the housing (1 a, 1 b) having an air inlet (4) and an air outlet (5), the insulating means (2) being arranged inside the housing (1 a, 1 b), and the at least one web (3 a, 3 b, 3 c) being arranged inside the housing (1 a, 1 b) such that said web projects at least partially into the insulating means (2), and air which flows from the air inlet (4) to the air outlet (5) through the housing (1 a, 1 b) is conducted into the insulating means (2) by the at least one web (3 a, 3 b, 3 c).
 2. The sound damper as claimed in claim 1, characterized in that the at least one web (3 a, 3 b, 3 c) is formed in one piece with the housing (1 a, 1 b).
 3. The sound damper as claimed in one of the preceding claims, characterized in that a first web (3 a) surrounds the air outlet (4) and/or a second web (3 b) surrounds the air inlet (5).
 4. The sound damper as claimed in one of the preceding claims, characterized in that the housing (1 a, 1 b) and the at least one web (3 a, 3 b, 3 c) are designed to be radially symmetrical about a common axis (6).
 5. The sound damper as claimed in one of the preceding claims, characterized in that the insulating means (2) contains a knitted roll (2) composed of a knit wound about an axis.
 6. The sound damper as claimed in claim 5, characterized in that the knitted roll (2) and the at least one web (3 a, 3 b, 3 c) are arranged so as to run parallel to one another.
 7. The sound damper as claimed in one of the preceding claims, characterized in that the at least one web (3 a, 3 b, 3 c) tapers at its end (8 a) projecting into the insulating means (2).
 8. The sound damper as claimed in one of the preceding claims, characterized in that the at least one web (3 a, 3 b, 3 c) has, in the region of its end projecting into the insulating means (2), one or more emergency passages for the passage of air.
 9. The sound damper as claimed in one of the preceding claims, characterized in that the air outlet (5) comprises at least one venting slot (5).
 10. The sound damper as claimed in one of the preceding claims, characterized in that the sound damper has a screen element (7) which is arranged in the region of the air inlet (4). 